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roads, and ahead-of-mining topsoil salvage). Subsequently, 9 to 15 <br />inches of loamy topsoil was replaced over light yellowish-brown <br />sandstone and light gray silts tone. This soil occurs on about 3.5 <br />percent of the study area (Table 9-4-3). <br />Chemical and physical properties of the replaced topsoil are suitable <br />(Tables 9-4-2 and 9-4-5). Coarse fragment contents range up to 35 <br />percent. The underlying IICR1 horizon is similar to regraded spoil for <br />sulfate and salinity levels. However, reaction values are more alkaline <br />for the IICRI material. This material will be salvaged as suitable <br />overburden during mining (see Tab 6, Addendum 6-1). Based upon nine <br />sampled profiles (Table 9-4-4), about 12 inches of suitable topsoil is <br />available for salvage within Map Unit 10. <br />Map Unit 11 - Sandstone Rock Outcrop, 6 to 35 Percent Slopes <br />This map unit is associated with the moderately to very steeply sloping <br />southwest facing sideslopes adjacent to premine drainages which dissect <br />• the study area. The sparse vegetation consists primarily of juniper, <br />prickly pear cactus, and forbs. Sandstone and shale bedrock outcrops <br />throughout this map unit. This map unit occurs in about. 21.5 percent of <br />the study area (Table 9-4-3). <br />No topsoil is available for salvage from Map Unit 11. First, slopes are <br />very steep and discontinuous. Second, approximately 60 to 70 percent of <br />the area has yellowish-brown sandstone, gray shale, and carbonaceous <br />shale outcrop material at the soil surface. <br />Map Unit 12 - Nontopsoiled Regraded Spoil, 6 to 35 Percent Slopes <br />This map unit occurs on moderately sloping to vary steep sideslopes. <br />Vegetation consists primarily of rabbitbrush, crested wheatgrass, <br />cheatgrass, saltbush, and forbs. This map unit, which occurs in areas <br />which were previously mined, graded, and seeded, represents about 6.7 <br />percent of the study area (Table 9-4-3). <br />With the exception of coarse fragments, the regraded spoil has suitable <br />to marginally suitable physical and chemical properties (Tables 9-4-2 <br />9-4-26 Revised 11/(11/86 <br />